SBIR-STTR Award

This effort will develop tracking algorithms and design tracking system compensations to operate under atmospheric scintillation. In September of 1997 a series of evaluation tests for three basic algorithms were conducted at Lincoln Laboratory over a range atmospherically scaled to the Airborne Laser scenario. The data showed that two major problems existed with the tracking algorithms, these were (1)scintillation was making calculation of tilt very difficult, and (2) the false tilt due to scintillation was being coupled back into system via the track loop control of the steering mirror. The test series at Lincoln Laboratories provide a large library of imaging data taken under scaled conditions of turbulence and scintillation. This project will use that data and develop new tracking algorithms and track loop designs to work under scintillated conditions. Several algorithms will be developed and completed, these are (1) spatial and temporal averaging routines, (2) a Kalman filter tracking algorithm, and (3) correlation algorithms. The best performing of the algorithms will be evaluated using a wave optics simulation.

This effort will develop and test tracking algorithms to operate under atmospheric scintillation. Phase I of this project developed evaluation techniques to determine the relative performance of various algorithms under scintillated atmospheric conditions and then tested 14 different algorithms and ranked them based on their performance. There were also data analysis techniques demonstrated in Phase I to help understand and analyze turbulence. In Phase II of this project, the algorithms will be extended to use subaperture wavefront data as well as full aperture data. Further, Phase II will include hardware and software implementations of the algorithms and field tests of the algorithms. A wave optics simulation will support the testing and evaluation of these tracking algorithms.

Keywords:
CORRELATION TRACKING KALMAN FILTER TRACKER SCINTILLATION SPATIAL SMOOTHING TRACK LOOP DESIGN TRACKER